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761.
We used a noninvasive monitor of arterial pressure to determine the utility of pulsus paradoxus (PP) as an objective severity measure in croup. We performed a prospective, blinded comparison of PP in children with croup versus healthy control subjects, analyzed the relationship between PP and Westley croup score (WCS), and observed the effect of racemic epinephrine (RE) on PP and WCS in a subgroup of patients with severe croup. The PP and WCS were measured at presentation and in severe patients after treatment with RE. Mean PP was 6.1 +/- 1.8 (SD) mm Hg (n = 29) in control subjects compared with a mean of 17.8 +/- 11.2 (SD) mm Hg (n = 28) in patients with croup (p < 0.00001). There was significant concordance between baseline WCS and PP (Spearman's rho: 0.68; p = 0.0001). The mean decrease in PP after RE was 7.5 +/- 11.8 (SD) mm Hg (p = 0.05; n = 12). The magnitude of decrease in PP after RE has significant concordance with the concurrent decrease in WCS (Spearman's rho: 0.73; p < 0.007). PP is elevated in children with croup, and the magnitude of elevation correlates with severity as measured by the WCS. PP may have utility as a research tool to objectively measure the severity of upper airway obstruction in croup.  相似文献   
762.
Antimicrobial susceptibilities of Neisseria gonorrhoeae have been prospectively determined in the Gonococcal Isolate Surveillance Project of the Centers for Disease Control and Prevention. From 1988 through 1994, susceptibilities were determined for 35,263 isolates from 27 clinics. Patients were demographically similar to those in nationally reported gonorrhea cases. In 1994, 30.5% of isolates had chromosomally or plasmid-mediated resistance to penicillin or tetracycline. Penicillin resistance increased from 1988 (8.4%) to 1991 (19.5%) and then decreased in 1994 (15.6%). Tetracycline resistance decreased from 1988 (23.4%) to 1989 (17.3%) and then increased in 1994 (21.7%). Most isolates (99.9%) were highly susceptible to broad-spectrum cephalosporins. Isolates with decreased susceptibility to ciprofloxacin increased from 1991 (0.4%) to 1994 (1.3%); 4 isolates were ciprofloxacin-resistant. Ciprofloxacin-resistant strains may not respond to therapy with recommended doses of fluoroquinolones, and the clinical importance of strains with decreased susceptibility is unknown. The emergence of fluoroquinolone resistance in N. gonorrhoeae in the United States threatens the future utility of this class of antimicrobials for gonorrhea therapy.  相似文献   
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764.
The purpose of this investigation was to measure the conversion of five inlay materials with different curing methods. In particular, the influence of secondary curing in light ovens--that is, additional curing with light and heat simultaneously--was evaluated. The conversion was determined by infrared multiple internal reflection spectroscopy. The inlays were cured with three curing methods (A, B, and C). The conversion was recorded immediately after ended curing and after an additional storage period (postcuring). The mean conversion with method A, using a handheld curing unit, was 42.1% and increased significantly to a mean of 55.4% during the storage period at (37 +/- 1) degrees C. Both curing methods B and C, including the use of light ovens, gave a mean conversion of 65%, which did not increase significantly during the storage period. This investigation demonstrated that the degree of conversion depends on the curing method used.  相似文献   
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766.
Lactoferrin, which exhibits antibacterial activity to protect infants from infectious disease, is a major component of colostrum and milk. Lactoferrin was purified from the colostrum of Korean Native goat, and the cDNA from the mammary gland mRNA of the animal was cloned and sequenced. The nucleotide sequence of the lactoferrin gene of Korean Native goat was found to differ in 15 sites from that of the goat lactoferrin gene reported earlier. This difference in nucleotide sequence resulted in six amino acid substitutions: five in the N-lobe and one in the C-lobe. The antibacterial activity of Korean Native goat lactoferrin was found to be greater than that of Sannen goat lactoferrin.  相似文献   
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768.
Mental depression and myocardial infarction (MI) are closely related. The current paper reviews pathophysiological mechanisms that could link depression to MI and discusses the pros and cons of different pharmacological and non-pharmacological treatment modalities that could be considered. The selective serotonin reuptake inhibitors lack arrhythmogenic effects, and have a beneficial effect in addition to depression on psychological factors, such as anxiety and mood disturbances, which are not uncommon in post-MI patients. Studies to further determine the impact of depression on the outcome of MI, and the place of different treatment modalities are in progress.  相似文献   
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